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The first early human eggs from stem cells

conception.bio

81–90 of 145 posts

Re: The first early human eggs from stem cells

#81

I am worried about the long term impact of research involving human conception, IVF, etc. The reason is that genetics/evolution don't yet seem to fully explain how humans exist. A computer genetic algorithm run for a billion generations doesn't lead to anything anywhere near the the complexity of a human. I suspect there are as-yet undiscovered effects which shape the next generation. Whether that be DNA methylation,…

Several of your claims are unsubstantiated. Sure, species co-evolve together, environment shapes evolution.

But why do you think evolution doesn’t explain existence of humans? What’s missing?

Also, as someone else has replied to you, we’re way past “natural” existence of humans. The vast majority of 8+ billions wouldn’t have survived in the past.

Re: The first early human eggs from stem cells

#82
post #77
post #71

Earlier quoted context omitted.

No, I don’t think so, because the egg still needs to be fertilized by a sperm cell to develop into an embryo. Now if the sperm cell were from the same donor I don’t know what would happen

> Now if the sperm cell were from the same donor I don’t know what would happen Probably nothing special except some inbreeding with the loss of 25% of genetic material of the donor individual (each gamete containing a random 50% of the donor's genetic material). Not sure how fast this level of inbreeding would be deleterious.

That's some Cleopatra-level inbreeding. The child's - or should we say the victim's - DNA would have longer runs of homozygosity than a child of incest.

Re: The first early human eggs from stem cells

#84

Earlier quoted context omitted.

I will let the experts continue from here :) This review is from 2020, i bet things have progressed since then https://pmc.ncbi.nlm.nih.gov/articles/PMC7169912/

It's not so much a mitochondrial transplant, as it is fertilized egg nucleus transplant. Not just mitochondria are used from the third donor but their whole egg (sans nucleus). So unless a human might develop from a bat egg just from swapping out nucleus, which I'm sure it's not the case, super-powered batman must remain a fantasy.

Oh, so that's what you were aiming for, LOL

there are many reasons for this chimera not to be viable, mitochondria co-evolves with the nuclear DNA, you can't just take a mitochondria from a totally different species

Re: The first early human eggs from stem cells

#85

I am worried about the long term impact of research involving human conception, IVF, etc. The reason is that genetics/evolution don't yet seem to fully explain how humans exist. A computer genetic algorithm run for a billion generations doesn't lead to anything anywhere near the the complexity of a human. I suspect there are as-yet undiscovered effects which shape the next generation. Whether that be DNA methylation,…

I think it’s important to remember that the process of selection acts directly on human traits. For example being exposed to high summer heat temperatures may eliminate some people who have unproductive sweat glands, or needing to run down your food may eliminate people who have a muscles that easily tire. Selection (largely) does not act on far removed traits like egg cell characteristics as a proxy of human traits like muscle performance because the genes that are used by egg cells are quite different than those used by muscle cells. So if you worry about some kind of human trait decline you should be much more worried that people have access to air conditioning and grocery stores.

Re: The first early human eggs from stem cells

#86
post #28
post #22

Earlier quoted context omitted.

You’re layering several hypotheticals on top of each other, which leads to progressively distant possibilities. Good on you for caring about humans though

I think this is decisively the wrong way to think about it. Yes, layering hypotheticals like that means that any one scenario is extremely unlikely to be the thing that gets you, but that doesn't mean the shape of the problem is wrong. It's like arguing with someone who doesn't believe in using seat belts when driving. "Why should I put them on?" they say, and when you try to explain what might go wrong they won't li…

"To play God" isn't just to do something spectacular which wasn't possible before. It's to use other people - to put yourself on a higher teleological level than other people, declaring their purpose (whatever it is) as fully subordinate to your purpose (whatever it is).

As if they were a tool you created. Obviously, if I carve a piece of wood into a spoon, it's I who get to say that what used to be a piece of wood now has a purpose of moving soup to mouths. The carved piece of wood now has a purpose, but it's wholly subordinate to my purpose (whatever it is).

You don't have to actually design people to play God - you can subordinate others to your purpose without doing that, that's what various God-kings in history did. But it certainly gives you a head start if you make them.

You can make something and don't subordinate it to your purpose. In our culture, we see children that way. We claim, basically, that we didn't deliberately design a child, we only obeyed our own natures without really having much choice in the matter, and thus we and our child is on the same teleological level.

This is not a cultural universal. In many cultures, parents (in particular fathers) would say basically "I made you, so you must do as I please, you have no reason for existing except for my purposes". It was a hard won battle for our culture to assert that children matter for their own sake and not just for their parent's.

Many things in this thread makes me want to say "Y'all MFs need Jesus". I won't say that, but I will say that you should stop and think about why it is that the Catholic church is so difficult about contraception, why Christians in general have historically made such a big deal of the difference "born of God" vs "Created by God" (arianism, etc.), and what that story of Abraham and Isaac was really about. Whether you agree or not, there's much about other people you will never understand if you don't think about teleological levels.

Re: The first early human eggs from stem cells

#87

Earlier quoted context omitted.

25% of humans died before reaching 5 in 1800s US, today it is We have not ended up with "humans which aren't as strong, aren't as smart, aren't as well adapted to a changing environment, etc."

I like the spirit of what you are saying but the smart part isn’t true at all. IQ peaked around the mid 1990s and as someone that lived back then that tracks. https://www.sciencedirect.com/science/article/pii/S016028962... Look at Fig. 3. The world seems to be experiencing a reverse Flynn effect.

IQ is not a unit, it's a z-score. Z-scores can only be compared within the same cohort against which they are computed and given the same test. Given that the cohorts and tests keep evolving over time, it makes no sense to track IQ across large time periods.

Re: The first early human eggs from stem cells

#88

I am worried about the long term impact of research involving human conception, IVF, etc. The reason is that genetics/evolution don't yet seem to fully explain how humans exist. A computer genetic algorithm run for a billion generations doesn't lead to anything anywhere near the the complexity of a human. I suspect there are as-yet undiscovered effects which shape the next generation. Whether that be DNA methylation,…

> A computer genetic algorithm run for a billion generations doesn't lead to anything anywhere near the the complexity of a human. What?... Our computers can't simulate anything similar to a real world. You're comparing apples to galaxies. > meaningful loss of fitness What makes you think we don't have "loss of fitness" already? 150 years ago child mortality was around 30% in the developed world, now it's less than 1…

It's a very common misconception that "survival of the fittest" means something related to physical fitness or stamina. It does not, in fact it's almost tautological. It means only "survival of those most likely to survive."

Natural selection is still fully in operation, but the things being selected for may have changed. Whatever they are now, they are still being selected for. Those most likely to reproduce are those whose who reproduce the most, and whatever those characteristics are, they will be the ones that become more prevalent.

It's also very important to remember that this operates over hundreds of millennia. Human beings changing substantially will not occur within a period of time less than that. You'd need to look back into deep prehistory to find changes to humans attributable to natural selection. Changes to modern humans are all explicable through changes to nutrition and lifestyle, not through evolution.

Re: The first early human eggs from stem cells

#89
post #28

Earlier quoted context omitted.

I think this is decisively the wrong way to think about it. Yes, layering hypotheticals like that means that any one scenario is extremely unlikely to be the thing that gets you, but that doesn't mean the shape of the problem is wrong. It's like arguing with someone who doesn't believe in using seat belts when driving. "Why should I put them on?" they say, and when you try to explain what might go wrong they won't li…

"I don't know if we have the terminology to talk about this kind of failure mode." We actually have and is called RISK. RISK = Probability * Damage. Applied to the seatbelt event we have a death level damage and a high probability of happening given recent studies, so using a simple belt could easily save you from deadly accidents. Applied to any unrealistic scenario we have insane level damages but also an incredibl…

Well that's the point about unknown unknowns though, we actually have no idea what the probability is. But we do know it's not low, that's the only unlikely scenario.

We only know it's a very complicated system with many interlocking dependencies, and based on what we know about complicated systems in general, as well as biology in particular, is that if any one of these unknown dependencies break, the whole system can fail catastrophically.

Therefore the probability that something will go wrong is very high, and the damage could easily be irreparable damage to the species, if not extinction. Does that not give an intolerably high risk?

Re: The first early human eggs from stem cells

#90
post #28

Earlier quoted context omitted.

I think this is decisively the wrong way to think about it. Yes, layering hypotheticals like that means that any one scenario is extremely unlikely to be the thing that gets you, but that doesn't mean the shape of the problem is wrong. It's like arguing with someone who doesn't believe in using seat belts when driving. "Why should I put them on?" they say, and when you try to explain what might go wrong they won't li…

"I don't know if we have the terminology to talk about this kind of failure mode." We actually have and is called RISK. RISK = Probability * Damage. Applied to the seatbelt event we have a death level damage and a high probability of happening given recent studies, so using a simple belt could easily save you from deadly accidents. Applied to any unrealistic scenario we have insane level damages but also an incredibl…

This framework would be hard to apply to unknown unknowns. That's why in software engineering you'd apply canarying. Then the longer timeframe for potential negative effects, the slower the adoption of a new process should be.
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